Vehicles are currently available which have free-pivoting front and rear sections so as to allow the two sections to rock laterally of one another about a fore-and-aft extending axis as may be required to maintain all four ground wheels engaged with the ground when uneven terrain is encountered. Typically, the free-rocking action is inhibited only by positive limit stops which function to positively preclude further relative rocking movement beyond a certain given amount of free travel.
While this feature is generally desirable, it may contribute to a less than desirable situation where one of the sections is provided with a lift capable of raising loads to relatively substantial heights above the ground. In such instance, if the front section to which the lift is attached is located on a lateral incline, then as the load is raised, the center of gravity of the combined load and front section becomes progressively more laterally disposed relative to the ground wheels of the section as the load is raised. Hence, the danger of tipover progressively increases as the load gets higher, and since the front section can rock freely relative to the rear section, the counterbalancing effect of the rear section cannot come into play until such time as the front section has started tipping and has reached the positive limit provided by the mechanical limit stop between the two sections. By then it may be too late to prevent a tipover considering the momentum of the load at the upper end of the elevated lift and the disposition of the center of gravity of the front section with its lifted load.